Clusters of galaxies are important cosmological probes. Since they
are dynamically young, it is possible that evolution could be observed
between a redshift of z \sim 0.3 to the present. We have used ASCA
data to determine temperatures for a sample of clusters at redshifts
of z \sim 0.3 and higher. The resulting distribution of
temperatures is consistent with the distribution of temperatures
obtained from analysis of nearby clusters. This suggests that cluster
temperatures do not evolve significantly up to a redshift of z \sim
0.3. We discuss the implications of these observations for some
current models of cluster formation and evolution.

The author(s) of this abstract have provided an email address for comments about the abstract: kenrines@rice.edu